U.S. Pat. No. 3,757,778, M. Graham teaches that EKG leadwires may be terminated in a wire distribution head which is connected by means of a cable to an EKG. The head includes lamps which indicate the effectiveness of connection of an electrode between the head and the patient. The patent recognizes the need for terminating EKG leadwires which cannot conveniently extend all the way to an EKG apparatus. While the Graham apparatus is useful, there is a need for further information at the distribution head. Often an operator has the need to evaluate signal quality as received by the EKG apparatus. Moreover, an operator may have a need to signal the EKG apparatus from a position close to the patient. For example, such signalling may initiate EKG measurements or terminate them.
Accordingly, there is a need for means of communicating with an EKG host system in order to receive data from the host indicative of signal quality, as well as providing a means for controlling the host operation.